1) Field of the Invention
The present invention relates to parallel processors computer system in general and in particular to the use of such computer systems in communications technology.
2) Prior Art
The use of parallel processing generically called multiprocessing is well known in data processing technology. In conventional data processing a plurality of processors are constrained to process subportions of a partitioned task and/or individual tasks in a set of tasks. The prior art abounds with multiprocessor patents, examples of which include:
U.S. Pat. No. 4,718,006
U.S. Pat. No. 5,021,945
U.S. Pat. No. 5,327,419 and
U.S. Pat. No. 5,692,119.
Even though multiprocessing systems are well known and used in data processing their use in communications technology is somewhat limited.
In this technology several problems have to be overcome if the system is to function satisfactorily. Among the many problems is that of sequencing. In particular, the sequence of data at the output of the system should be the same as when the data was received at the input. The proper sequencing of data is particularly difficult in communications technology in which the data is delivered in units called a frame or packet which can be of different lengths.
Because of the difference in frame length, among other things, a processor could complete processing a short frame in less time than is required to process a long frame. As a consequence the processed short frame would be available at the output of the system before the processed long frame even though the sequence at the input was long frame followed by short frame.
To maintain the sequence the prior art uses complicated circuits to keep track of the sequence at delivery and at the output organizes the processed frames in the same order in which the frames were delivered at the input of the system. These circuits are costly and increase the cost of the system. In addition, additional silicon space is required to implement the circuits. In most designs silicon space is a scarce commodity and should be preserved whenever possible.
Another problem is throughput. In most communications networks data is received from a network operating at a particular data rate process by a receiving system and returned to the network. Usually, the processing rate of the receiving system is much slower than the data rate of the network. The discrepancy between data rates results in a bottleneck within the receiving system. In some applications the bottleneck is a negative that cannot be tolerated. As a consequence there is a need to provide receiving systems with throughput matching that of the network to which the receiving systems are connected.